This plant displays densely set leaves that are short, narrow and pointed, appearing bright green in colour with silvery hues. Tonina Fluviatilis is perfectly set in the aquarium midground with Syngonanthus species, which share the same requirements.
It is moderately difficult to grow well, requiring medium to intense lighting, regular fertilisation, soft, acidic water and high levels of injected CO2 for optimal growth. An acidic substrate such as aquasoil is also suggested.
T. fluviatilis makes many special demands on the hobbyist, making it unsuitable for beginners. This stem plant requires at least moderately soft water in order for it to thrive; a GH of about 5 or less should be adequate. The substrate material should be acidic (such as Florabase, or ADA Aquasoil), although a mature Eco-complete or Flourite substrate with a peat under layer will suffice. Lighting should be intense (3 watts per gallon or more). CO2 injection is a necessity for this plant to thrive as well. Surprisingly, T. fluviatilis is not all too fussy about water column fertilization other than ample additions of iron/micronutrients. However. do not let nitrate and phosphate levels reach zero. Because of this plant's special demands, some hobbyists choose to set up a special aquarium just for it and other soft water, acidic substrate loving species (Syngonanthus spp., Eriocaulon spp., etc.).
T. fluviatilis grows vertically even under very intense light, setting out the occasional side shoot along the length of the stem. Because of its moderate growth rate, it can be smothered by more competitive, faster growing stem plants; make sure that it does not get shaded. When this plant grows too tall, simply top and replant the more robust top portions. To propagate, snip off the side shoots with a pair of scissors and replant. Replant only the top two inches of each stem for best results, as starting with trimmings that are too tall will result in the lower portions becoming rooty and ratty. Shorter trimmings will grow out into cleaner, healthier looking stalks.
This Tonina species is an excellent green accent plant in the mid ground to background of an aquascape because of its unique, fresh green foliage. It would be an excellent candidate for a Dutch style tank, because of its moderate growth rate, very vertical growth habit, and adjustable height.
* FoR the plants long known as Tonina sp. 'Belem' and Tonina sp. 'Manaus', please see the genus Syngonanthus